Method for preparing a parison and transferring it to a molding machine

A method of preparing a parison that is continuously extruded in an extrusion direction from an extrusion head and for transferring sections of said parison to a stationary molding machine mounted at a location laterally displaced from and below said extrusion head, said method comprising the steps of:

• A. preparing said parison by cyclically,
• 1. at a parison receiving position, grasping and sealing said parison at one location on its length;
• 2. stretching said parison, while it is extruded, by moving said one location in said extrusion direction to a remote position at a controlled rate;
• 3. releasing said one location of said parison;
• B. severing and transferring said parison by cyclically,
• 1. after said parison has again been grasped and sealed at the parison receiving position in said cyclical parison preparing step, at a parison accepting position spaced farther from said extrusion head than is said parison receiving position, grasping and sealing said parison at a second location on its length intermediate said one location and said extrusion head to thereby define a parison section between said locations;
• 2. severing said parison section from said parison by transferring it transversely to said extrusion direction away from said extrusion head;
• and
• 3. delivering said parison section in a direction generally parallel to said extrusion direction, to said molding machine and releasing it therein.

A method of preparing a parison that is continuously extruded in an extrusion direction from an extrusion head and for transferring sections of said parison to a stationary molding machine mounted at a location displaced from said extrusion head, said method comprising the steps of:

• grasping and sealing said parison at one location on its length;
• stretching said parison, while being extruded, in said extrusion direction by moving said one location away from said extrusion head at a controlled rate;
• releasing said one location of said parison;
• grasping and sealing said parison, after being stretched, at a second location on its length intermediate said one location and said extrusion head;
• grasping and sealing said parison at a third location intermediate said second location and said one location to thereby define a parison section between said one and third locations;
• transferring said parison section away from said extrusion head to sever said parison section from said parison between said second and said third locations;
• and
• delivering said parison section to said molding machine.

The method of preparing an extruded parison for transfer to a molding machine as the parison is produced from an extrusion head comprising the steps of

• grasping the parison at a first location on its length,
• stretching the parison by moving the first location away from the extrusion head at a controlled rate,
• after said stretching, releasing the first location of the parison and grasping the parison at a second location toward the extrusion head with one means for grasping the parison,
• grasping the parison at a third location between said first and second locations with a second means for grasping the parison to define a parison section between said first and said third locations,
• moving said second grasping means away from said one grasping means to tear and sever said parison between said grasping means, and
• delivering the severed parison section to the molding machine.